I am familiar with the brands you are asking about.

In addition to the brands you have listed there are others that may work for you, but that depends on the size and configuration you are looking for.

If you are looking for a sectional with 3 seats and an ottoman, there will be a lot more selection than if you need 4, 5, or 6 seats plus ottoman.

You can see some of these alternative brands at 58 Quality & Value Ratings for Sofas & Sectionals 2023.

1. Sactionals will exceed your price range. At the same time, the quality is no better than Crate and Barrel. Check out Is Lovesac quality worth the high price?
2. West Elm has a very high rate of customer complaints. It is your worst choice of the listed brands.
3. The biggest factor limiting the long-term durability of most mid-priced (mass produced) sectionals will be the cushions. 

Cushion durability and lifespan will depend on:

• Foam density
• How much you weigh.
• The amount of use the cushions get.
• The size of the cushions (Larger cushions last longer.)

Most of the brands you have listed come with 1.8 density foam cushions. Any cushions listed as "high density foam", without any other description will be 1.8 density.

Cushions described as "high density sponge" are 1.8 density foam fabricated in Asia. (Asian foam is less consistent and usually lower quality than U.S. made foams.)

Foam density is critical to cushion durability. 

Higher density cushions cost more and weigh more. For example:

• 1.8 density foam cushions have an average lifespan of 3 - 5 years before losing their shape, resilience (ability to bounce back) and comfort.
• 2.5 density foam (usually found only on high end custom-built pieces) have an average lifespan of 15+ years.
• Cushions with coil spring construction will last longer than foam.

Low end coil spring cushions (such as those found on the Belffin modular sectional and some Crate and Barrel sectionals), should last 8 - 10+ years.

High end coil spring cushions (not available on any of the brands you listed) will retain their shape and comfort for 20+ years.

4) Crate and Barrel and Room and Board are better quality overall than the other brands you have listed (other than the very expensive Lovesac.)

But the long-term durability of these two brands is limited by the 1.8 density foam cushions found on most of their models.

Some C&B models, such as the Gather sectional, use coil spring cushions that will double the cushion lifespan.

Any Crate and Barrel or Room & Board sectionals that are made with coil spring cushions should last 10+ years (twice as long as models with 1.8 density foam cushions.)

5) Burrow overall quality is below Crate and Barrel.

The biggest problem is that Burrow is using composite 3 layer foam cushions, with a dense central core surrounded above and below by lower density layers.

See my article, Review of Allform vs. Burrow for more details.

Several brands switched to this composite cushion construction about 3 years ago. At the time the multi-layer cushions were introduced, I wrote several articles questioning whether they would last even 3 years.

It is now 3 years later. Some of the brands that switched to multi-layer cushion construction (including Flexsteel) have now changed back to solid core 1.8 density cushions. 

6) I like Honbay's storage functionality, but the frame is suboptimal and the sectional's lifespan is limited by the 1.8 density "foam sponge" cushions. The cushions will probably wear out within 3 - 5 years.

7) The Belffin modular storage sectional appears to be a good combination of quality, value and durability. 

It has unusual functionality, including both storage beneath every seat and adjustable backs and arms.

But what really makes this a good "buy" for me is the coil spring cushions.

These extend the sectional's lifespan to 6 - 8+ years.

I would have estimated 8 - 10+ years, but I am uncertain about the durability of the unusual adjustable frame. 

I don't think all the Belffin models have the coil spring cushions, so you need to verify that if you choose a different model.

Check out this video review that compares Honbay vs. Belffin. 

The creator of the video rates Honbay over Belffin, but for some reason she is comparing the 4 seat Honbay modular storage sectional to a smaller 3 seat Belffin non-storage sectional. 

Her main deciding factor seems to be the storage functionality, which was not available in the Belffin piece she is comparing. 

The Honbay should have been compared with the Belffin modular storage sectional.

In this comparison, the Belffin matches the storage capability and also has the added functionality of reclining backs and arms.

When you add in the coil spring cushions, which double the lifespan over Honbay's 1.8 density "sponge" cushions, Belffin should be the clear winner.

There are a couple of possible negatives to the Belffin modular storage sectional sold by Amazon.

• I would not recommend the Belffin sectional for anyone weighing 250 lbs. or more. 
• The frame is flimsy and the movable backs and arms are probably less durable than solid (non-adjustable) backs and arms.
• The velvet fabric is highly durable and easy to clean. (It does not need added Scotchguard.) But the velvet is a magnet for dust and pet fur.

Summary:

Several of the brands listed have sturdy frames that will hold up for 10 - 20+ years, but that is insignificant when combined with 1.8 density foam cushions that will wear out in 5 years or less.

Crate and Barrel's Gather sectional (and possibly some of their other models) has a sturdy frame and coil spring cushions that should last 10+ years.

Belffin is 1/2 the price and should also last 10 years if used gently.